Precision engraving instrument



Oct. 29, 1957 Q. s. JOHNSON ET AL PRECISION ENGRAVING INSTRUMENT 2 Sheets-Sheet 1 Filed July e, 195e m 5 mw. n NsH N ENA R WHC w b I0 2 JH y if .3 mm ww Y f B Oct. 29, 1957 Q. s. JOHNSON ETAL 2,810,960

PRECISION ENGRAVING INSTRUMENT Filed July 6, 1956 y2 Sheets-Sheet 2 Z9 IN VEN TORS QUE/V 77N S. JOHNSON W/l. L I A M H. CARR AUDE/VHS United States Patent 2,810,960 PRECrsIoN aNGRavING INSTRUMENT Quentin S. Johnson, Alexandria, and William H. Carr, Woodbridge, Va., assignors to the United States of America as represented by the Secretary of the Arnay Application July 6, 1956, Serial No. 596,37 0

7 Claims. (Cl. 33-1.8)

(Granted under Title 35, U. S. Code (1952), sec. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

The present invention relates to a device for producing engraved or inscribed linework in or upon various materials for use in the graphic arts. More particularly, the present invention relates to such a device for engraving or inscribing lineworl; in or upon paint, ink, gelatinous emulsion, dyed vehicles, or other materials, applied as a coating upon plastic sheeting, glass sheets, metal sheets or plates, paper, wood, or stone materials.

Existing engraving or inscribing instruments, tools, or other devices are so designed as to be dependent upon the skill of the operator (in the case of existing hand-held devices), or upon costly, heavy, and/ or bulky mechanical linkages (in the case of existing mechanical engraving or inscribing devices) for maintenance of optimum pressure at the engraving or inscribing cutting point, in order to produce linework (linewidth) of uniform weight. rIhis invention, which combines in a single hand tool the properties of continuous mechanical control of point pressures t (usually associated with large mechanical linkages) and versatility, portability, direct operator control, and relatively low cost typical of the class of hand tools, therefore embodies the major desirable features of an optimum engraving or inscribing instrument.

An object of the invention is to provide a suitable handheld and hand-operated device for engraving or inscribing operations, having included therein a mechanism for maintaining a constant pressure at the engraving or inscribing cutting point independent of the pressure exerted by the hand of the operator during use, which mechanism includes means for adjusting the cutting point pressure to that required for the material being engraved or inscribed.

Further objects of the invention will become apparent from the drawings and from the following detailed description of the invention, the accompanying drawings being intended to be illustrative of a preferred or typical embodiment of the improvements of the present invention without thereby tending to limit the scope of the invention to less than that of all of those equivalents which will be apparent to those acquainted with the art as defined by the appended claims, it being noted that throughout the drawings like reference numerals refer to like parts.

ln the accompanying drawings- Fig. 1 is a perspective view of the device of the invention;

Fig. 2 is a vertical view, partly in section, of a portion of the device of Fig. 1;

Fig. 3 is a vertical sectional view showing a form of mounting means for the instrument as shown in Fig. 1, the view being taken on line ill-lil of Fig. l, looking in the direction of the arrows;

Fig. 4 is a view similar to Fig. 3, but showing a modication thereof;

Fig. 5 is a further view similar to Fig. 3, but showing a further modification thereof;

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Fig. 6 is a perspective view of a weighting device or attachment for the device or tool of Fig. `l;

Fig. 7 is a perspective view of an oli-setting holder for a scribing device, the view being a modification of the holder shown in Fig. l;

Fig. 8 is a plan view of a magnifying lens usable on the device of Fig. 1;

Fig. 9 is a vertical sectional view through the lens, the view being taken on the line lX-lX of Fig. 8, looking in the direction of the arrows; and

Fig. 10 is a further vertical sectional view through the lens, the view being taken on the line X-X of Fig. 8, looking in the direction of the arrows.

Referring more particularly to the drawings, the illustrated embodiment of the invention includes a shaft or spindle 1li which is mounted on and carried by a base block by a retainer ring 1S formed at the intersection of outwardly extending converging brackets 18) projecting from the ends of `base block 15 which is shown as having an approximately horseshoe shape. The shaft 10 carries 'at its lower extremity an adjustable point-chuck Vin which may be fixed, by means of a Vset screw 12, an engraving or inscribing stylus or cutting point 13. The shaft ll is provided at its upper extremity with an adjusting nut or sleeve 14 by means of which the pressure at the cutting point i3 may be adjusted by a compression spring or other mechanism concealed in Fig. 1 inside the shaft lil. In Fig. l, the base 'block 15 is shown mounted on three mounting feet including freely turnable ball elements 16 mounted in retaining holders 182 and providing equally spaced three-point mounting for the base block 'l5 and the instrument. The freely rotatable ball element i6 permit the device held in an operators hand to be moved laterally in any direction over a surface 17 into or upon which engraving or inscribing 134 may be accomplished by cutting point point or stylus i3.

Referring now to Fig. 2, there is shown a detailed vertical view, partially sectionalized, of the shaft or spindle ii) and the shaft retainer ring 18 of the base block 15, shown in Fig. 1. The shaft it) may be positioned substantially vertically in base block 15 by means of external screw threads 19 on shaft lil which fit into internal threads 20 in shaft retainer ring 18, and may be secured at the desired vertical position in shaft retainer ring 18 by means of a lock nut 2i. Cutting point 13 may be positioned in point chuck il and fixed in position therein by means of set screw l2. The pressure exerted by cutting point 13 on surface i7 into or upon which engraving or inscribing Lid is to be accomplished, then may be adjusted to that desired by means of anadjusting uut or sleeve i4 acting through a compressing coil spring 22, a thrust bearing 23, and a sliding internal shaft or piston 24 rotatably mounted in shaft l@ by means of bearing 25. Piston 2d may contain a longitudinal groove 26 in which may be positioned a pointed set screw 27 passing through the Wall of shaft lil, which set screw 27 may be so positioned as to permit piston 245 to move longitudinally but not rotatably when the set screw 27 projects into the groove 26. rifhe set screw 27 may be so positioned as to permit both rotational or longitudinal movement to piston 24 when its projection into the interior of shaft 10 is insufficient to permit the point of set screw 27 from entering into the groove 26, lt is obvious that the set screw 27 may be tightened to engage and lock the piston 24, if desired, against rotational and longitudinal movement although this is not the normal manner in which the set screw 27 is employed.

Figs. 3, 4, and 5 show modifications of the three-point mounting for the base block i5. As pointed out above, such mounting may be ball-bearing feet 16 freely rotatable in retaining holders 82. These ball-bearing feet 16 may be replaced by miniature freely rotatable casters 28, or

Yof resistance to lateral motion of the instrument in use on various materials. Y*

Fig. 6 shows a perspective view of a weight 3S so shaped as to t within the body of the base block 15, that is, be-

tween therbracket arms 189 of Fig. l, in such a manner as to provide a Weight on the device ysufficient to compress spring 22 and to maintain all three of the mounting feet of Figs. 3, 4, and 5, such as the ball-bearing rollers 16, in contact with work surface 17 without exertion of any hand pressure by the operator to maintain such contact. A series of such weights'38 may be provided iny various size s as Vmay be required to accomplish the objective, each of such weights having a cylindrical body portion 185 insertable between bracket arms 180 with top collar or flange 188 resting on top of the bracket arms 180` Weights, such as 38, are employed when the pressure required'by vspring 22 to scribe heavy or multiple lines is greater than the mass of the unweighted instrument and causes the unweighted instrument to become unstable. The set screw 27 is not locked or in rigid contact with the piston 24 whether operating with or without weights, such as 33. The tip of set screw 27 is adjusted to enter the groove 26 in piston 24v onlyV far enough to restrict rotational motion of the piston 24 and the attached scribing point 13 during scribing operations where non-swiveling action is desired, while permitting the piston 24 to move longitudinally. Contact of the tip of set screw 27 occurs only at one side or the other of the groove 26 to limit rotation of the piston 24 to that angle permitted by the clearance Vbetween the sides of the groove 26 and the diameter of theipointed tip of set screw 27.

With reference to Fig. 7, there is shown a perspective view of an attachment 32 for point-chuck 11, permitting the cutting point 13 to be mounted in the tool of Fig.'1 at a distance Yoff-set from the longitudinal axis of shaft 1i), thus providing'for swiveling of cutting stylus 13 or rotation of such stylus about such axis'when setY screw 27 of Fig. 2 is backed olf sufficiently to `be disengaged from groove Zdin piston 24 of Fig. 2. Resistance of the surface 17 into or upon which cuttingV point 13 is engraving or inscribing, in this instance will cause the cutting point 13.to maintain a constant orientation with respect to the line orlines 184 being engraved or inscribed in surface 17,

irrespective of the direction of lateral motion of the deviceofFig. 1. v

`There may be provided a detachable viewing lens 34 which maybe attached to or removed from shaft 1G, as -shownin Fig. l, by means of slot 35 having clip spring 36 iixedly mounted therein adjacent to its inner end. The

Vouter Vend `of slot 3S is formed with diyerging guide surfaces 37 for guiding the lens onto the shaft 19 and prof viding unobstructed removal of thelens from the shaft 10.

-It will be understood that the accompanying drawings and the foregoing detailed description thereof are to be regarded as being illustrative only of a preferred embodiment of the improvements presented by the present invention, and that various structural details Vare subject Vto differences which will become apparentto one skilledin the art to whichthe invention relates, without departingY from thespirit of the invention, and accordingly, it will be understood'that it is intended and desired to embrace within the scope of this invention such modifications and changes as may be necessary Vto adapt it to varying conditions tand uses, as defined by the appended claims.

. to engage a work surface being engraved, resilient self-em-l bodied compression means mounted within the holder and engaging said elongated member for continuously exerting a constant outward pressure on the stylus for continuously Vand constantly Vpressing the stylus into constant engraving pressure against the work surface for imparting Y linework engraving pressure between`the stylusand the work surface, mounting means for adjustably carrying said holder and maintaining the stylus perpendicular to the Vwork surface, a longitudinal recess in said elongated member and means extending'through said holder and projecting into said recess sfor limiting the degree of rotation about the longitudinal axis of said elongated mem-v Y ber within said holder. Y

2. An engnaving tool comprising, in"combination`, a tubular engraving holder adapted to be moved manually over a work surface to be engraved with, line-work, an

elongated member having an upper and a lower end slidably carried within said holder for relative movement therewith, an engraving stylus carried by said elongated member Vadjacent to its lower end and adapted to engage a work surface being engraved, Vcompressed Vresilient means housed in the holder and pressing against the upper end of sai-d elongated member for continuously exerting -a constant outward pressure on the stylus for continuously and constantly pressing the stylus into constant engraving pressure between the stylus and the work surface, a longitudinal recess in said elongated member and means extending through said holder and projecting for limiting` the degree of rotation about the longitudinal axis of said elongated memberY within said holder, a base block for mountingV the holder including a plurality of equally spaced sockets formed in the under surface of said block and means slidably received in each of said sockets, adjusting means in said block communicating with each of said sockets for connection to'each of `said mounting means for varying Y the distance each of said mountingmeans projects vertically beyond the under surface of said base block, each of said mounting means including an element having a curved surface contacting the work surface, horizontally disposed bracket arms convergingly'extending from the base block and converging into a holder-receiving'ring, the said holder engaging the ring adjacent to the lower end of the holder, the said ring and bracket arms mounting the holder in off-set relation with respect to the base block, cooperating threads in the ring and on lower portions of the holder for enabling adjustment of the holder, elongated member and stylus together n a vertical pl-ane with respect to the work surface being engraved, an ad-Y justable closure cap for the upper end of the holder, and mechanism in the holder actuated by adjustment ofthe closure cap for selectively adjusting the" pressure main.- tained on the stylus by the stylus-pressing means from one constant value to another.

3. The engraving'tool construction as claimed in claim 2, wherein the stylus-pressing means include ka pressure Having thus described Vour invention, what we vclaim Yas new and wish to secure by Lettersl Patent is:

l. An engraving tool comprising, in combination, a tu- `Ybular engraving holder adapted to be moved manually over a work surface to .be engraved with line-work, an elongated membercarried within said holder for relative movementtlrerewith, an engraving stylus carried by said elongated member adjacent to its lower end and adapted compressed' coil spring in the holder, maintained com-V pressed by the closure cap, said elongated member transmitting pressure of the compressed spring tothe stylus, continuously urging the stylus outwardly with respect to the holder under a selected constant force.

4. The engraving tool construction as claimed in claim 3, Ywherein theY compressed spring acting onthe stylus is compressed between @an'upper piston and a lower piston, said lower piston including a recessed portion, free rolling bearing means seated in said recess and supporting the upper end Vof said elongated member, the upper piston exerting an adjustable constant pressure on the spring in accordance with selected adjustment of the closure cap, the spring -transmitting suchpressure to the lower piston secured. to the upper end of said elongated member, chuclg means carriedat the lower end of said elongated miember holding the stylus in extended position Vrelative to the holder and operated by the lower piston. Y

5 6 5. The engraving tool construction as claimed in claim References Cited in the le of this patent 4 wherein the elongated member is supported for rotation UNITED STATES PATENTS about the longitudinal axis thereof in free rolling bearing suPPOTS and Said Chuck means located at the lower and 611,625 Goddard Oct, 4, 1898 of Said elongated member iIlCllldeS a Stylus-holding afm 5 9 391597 Hurst NOV. 9, exteldng lalally relative to the elongated member for 1,276,793 M111-Ch311y Allg. 27, 1918 Oisetting the stylus relative to the 10ngitudina1 axis of fue 1,649,966 Marlottr Nov. 22, 1927 elongated member. 1,707,914 Lampe Apr, 2, 1929 6. The engraving tool construction as claimed in claim 23111234 KaJC Feb- 16, 1943 2 further including a weight insertable between the bracket 10 2,413,274 Wllkle et al Dec. 24, 1946 arms intermediate the base mock and homemacaiving 2,497,418 Schroeder Feb. 14, 195o ring and mountable on the bracket arms for incl-easing 2,567,049 Belluche Sept. 4, 1951 pressure on the stylus by the stylus-pressure means within 2,734,272 Brown Feb. 14, 1956 the tubular holder. 2,735,177 Adams Feb. 21, 1956 7- The engraving tool construction of claim 6 wherein 15 2,744,329 Way et a1. May 8, 1956 the weight includes a body portion insertable between the 2748474 Bmwn 11111@ 5, 1956 bracket arms and a top flange spanning the bracket arms and engageable therewith for suspending the body portion on the bracket arms. 

